MongoDB - ReplicaSet - Failed to refresh key cache

I am deploying my first replica set on a Windows 10 machine with MongoDB 5.0. For the purpose of the tutorial, I want all the servers running on my machine, on different ports.

A)

I created my first server with :

mongod --replSet rs0 --port 27018 --dbpath C:\data\R0S1

I opened another command line prompt and I connected to it with mongo --port 27018. I iniated the set with the command rs.initiate().

B)

I created my second and third server with :

mongod --replSet rs0 --port 27019 --dbpath C:\data\R0S2
mongod --replSet rs0 --port 27020 --dbpath C:\data\R0S3

(I ran each of these commands in new command line prompts)

C)

I added the second and third server to the set by connecting to the primary server (on 27018 with mongo --port 27018) with :

rs.add("localhost:27019")
rs.add("localhost:27020")

At this stage, everything has worked as expected. Running rs.conf() gives me :

{
        "_id" : "rs0",
        "version" : 5,
        "term" : 1,
        "members" : [
                {
                        "_id" : 0,
                        "host" : "localhost:27018",
                        "arbiterOnly" : false,
                        "buildIndexes" : true,
                        "hidden" : false,
                        "priority" : 1,
                        "tags" : {

                        },
                        "secondaryDelaySecs" : NumberLong(0),
                        "votes" : 1
                },
                {
                        "_id" : 1,
                        "host" : "localhost:27019",
                        "arbiterOnly" : false,
                        "buildIndexes" : true,
                        "hidden" : false,
                        "priority" : 1,
                        "tags" : {

                        },
                        "secondaryDelaySecs" : NumberLong(0),
                        "votes" : 1
                },
                {
                        "_id" : 2,
                        "host" : "localhost:27020",
                        "arbiterOnly" : false,
                        "buildIndexes" : true,
                        "hidden" : false,
                        "priority" : 1,
                        "tags" : {

                        },
                        "secondaryDelaySecs" : NumberLong(0),
                        "votes" : 1
                }
        ],
        "protocolVersion" : NumberLong(1),
        "writeConcernMajorityJournalDefault" : true,
        "settings" : {
                "chainingAllowed" : true,
                "heartbeatIntervalMillis" : 2000,
                "heartbeatTimeoutSecs" : 10,
                "electionTimeoutMillis" : 10000,
                "catchUpTimeoutMillis" : -1,
                "catchUpTakeoverDelayMillis" : 30000,
                "getLastErrorModes" : {

                },
                "getLastErrorDefaults" : {
                        "w" : 1,
                        "wtimeout" : 0
                },
                "replicaSetId" : ObjectId("61cc297329dca2f0673c2cff")
        }
}

D) In a new command line prompt, I create my fourth server (with the idea of making it an arbiter) with :

mongod --replSet rs0 --port 30000 --dbpath C:\data\arb

Here I have a problem. The log file for this new server contains the following error :

{"t":{"$date":"2021-12-29T10:50:51.767+01:00"},"s":"I", "c":"-",
"id":4939300, "ctx":"monitoring-keys-for-HMAC","msg":"Failed to refresh key cache","attr":{"error":"NotYetInitialized: Cannot use non-local read concern until replica set is finished initializing.","nextWakeupMillis":19200}}

When connecting to the primary and trying to do "rs.addArb(localhost:30000)", the command blocks and does nothing, because of the above error on server on port 30000 I believe.

Do you have any ideas on what's going on and how I could solve my issue ?

---- edit 1 ----

below is my mongod.cfg file :

# mongod.conf

# for documentation of all options, see:
#   http://docs.mongodb.org/manual/reference/configuration-options/

# Where and how to store data.
storage:
  dbPath: C:\Program Files\MongoDB\Server\5.0\data
  journal:
    enabled: true
#  engine:
#  wiredTiger:

# where to write logging data.
systemLog:
  destination: file
  logAppend: true
  path:  C:\Program Files\MongoDB\Server\5.0\log\mongod.log

# network interfaces
net:
  port: 27017
  bindIp: 127.0.0.1


#processManagement:

#security:

#operationProfiling:

#replication:

#sharding:

## Enterprise-Only Options:

#auditLog:

#snmp: